1. Field of the Invention
The present invention is generally related to a marine propulsion system and, more particularly, to a marine propulsion system that allows the engine and drive unit to be attached together prior to assembly into a marine vessel.
2. Description of the Related Art
Many different types of marine propulsion systems are known to those skilled in the art. These include sterndrive systems, inboard propulsion systems, and outboard motors. Sterndrive propulsion systems are assembled in a marine vessel by individually mounting the engine within the marine vessel, mounting the drive unit to an outer surface of a transom of the marine vessel, and then attaching the engine output shaft to an input shaft of the drive unit.
U.S. Pat. No. 4,634,391, which issued Entringer et al. on Jan. 6, 1987, discloses an engine coupler for a sterndrive. A coupling assembly for coupling the crankshaft of an inboard engine to the input shaft of an outboard propulsion unit has a coupling member stamped from steel. The coupling member is attached to the engine flywheel at three points at the vertices of the triangular coupling member base. An elastomeric annulus couples the coupling member to the input shaft.
U.S. Pat. No. 4,297,097, which issued to Kiekhaefer on Oct. 27, 1981, discloses a sterndrive mechanism. The sterndrive installation includes a mounting bracket assembly for securement to the transom of a watercraft. The bracket assembly is provided with a transverse horizontal bore rearwardly of the transom for receiving one end of the horizontal cylindrical portion of the upper housing of the drive unit. A bracket assembly addition is provided with a horizontal bore which rotatably receives the opposite end of the horizontal cylindrical portion of the upper housing and is secured to the bracket assembly.
U.S. Pat. No. 4,362,514, which issued to Blanchard on Dec. 7, 1982, describes a high performance sterndrive unit. A marine propulsion device comprises a bracket adapted to be fixed to a boat transom. It has an upper portion and a lower portion. A propulsion leg includes a rotatable mounted propeller. A first ball joint universally connects the propulsion leg and the lower bracket portion. A hydraulic cylinder-piston assembly has first and second ends. A pivot connects the first end of the hydraulic cylinder-piston assembly to the propulsion leg about an axis which is generally horizontal when the bracket is boat mounted.
U.S. Pat. No. 4,178,873, which issued to Bankstahl on Dec. 18, 1979, discloses an exhaust coupling assembly for a marine sterndrive. The drive includes an inboard engine having an exhaust passageway connected to an outboard drive unit having an exhaust passageway. A transom bracket assembly is positioned between the engine and the drive unit and permits vertical pivoting of the drive unit for steering and horizontal pivoting of the drive unit for trimming. The improvement includes a first exhaust pipe connected to the inboard engine and a second exhaust pipe connected to the drive unit.
U.S. Pat. No. 3,669,057, which issued to Shimanckas on Jun. 13, 1972, describes an inflatable transom ceiling arrangement. A boat hull has a transom having an aperture. A sterndrive unit is mounted on the boat hull and has a part extending through the transom aperture. A seal extends between the transom and the part and comprises a member which is inflated so as to sealingly circumferentially engage both the part and the transom to prevent passage of water through the aperture and around the part into the hull.
U.S. Pat. No. 6,491,588, which issued to Mansfield et al. on Dec. 10, 2002, describes an upper case housing support tower for a marine sterndrive unit. The support is a generally tubular member of high quality steel or steel alloy which is threaded at its lower end. The upper end carries an external flange. The upper end defines an internal taper which receives a bearing assembly. The flange is secured in the unit by a fastener and the threaded lower end is secured by a retainer such as a spanner nut. The driveshaft extends within the support substantially increasing the horsepower capacity of the unit by several times.
U.S. Pat. No. 6,607,410, which issued to Neisen et al. on Aug. 19, 2003, describes a single cylinder tilt-trim assembly for boats using a sterndrive system. The system includes a gimbal ring that defines an inner region. The gimbal ring is configured to pivotally receive a first anchor pin. A tilt-trim assembly is affixed to the outdrive and the tilt-trim assembly has one respective end thereof configured to pivotally receive a second anchor pin supported by the outdrive.
U.S. Pat. No. 6,305,997, which issued to Whiteside et al. on Oct. 23, 2001, describes a self-aligning universal joint assembly for a sterndrive. A U-joint includes an input shaft that receives driving power and an output shaft connectable to the drive unit. The assembly further uses an alignment subassembly configured to support the U-joint in an alignment position while its output shaft is being connected to the drive unit.
U.S. Pat. No. 4,940,434, which issued to Kiesling on Jul. 10, 1990, discloses a marine propulsion unit universal drive assembly with through-bellows exhaust. A pair of generally telescoped bellows surround the universal joint of a marine propulsion device and provide an exhaust passage therebetween which communicates between the inboard engine and the sterndrive unit. In an embodiment, the inner bellows rotates with the universal joint while the outer bellows is stationary.
U.S. Pat. No. 4,897,057, which issued to McCormick on Jan. 30, 1990, discloses a marine propulsion unit universal drive assembly. A flexible bellows surrounds the universal joint disposed between a marine engine and a sterndrive unit. It is mounted to rotate with the universal joint itself. The universal joint is disposed within a chamber delineated by the bellows itself and by end caps mounted to the universal joint shafts.
U.S. Pat. No. 6,296,535, which issued to Bland et al. on Oct. 2, 2001, describes a tilt-trim subsystem for boats using a sterndrive system. The subsystem assembly is affixed to an outdrive of a sterndrive that may be supported by a gimbal unit and may be configured to rotate about a predetermined axis to impart a desired trim or tilt to the drive system. The tilt-trim assembly has one respective end thereof configured to pivotally receive one anchor pin supported by the outdrive. The assembly includes one or more cylinders having one end thereof pivotally connected to another anchor pin so that when the cylinder is actuated the outdrive and the tilt-trim subsystem assembly are jointly rotated about the predetermined axis.
U.S. Pat. No. 6,454,620, which issued to Theisen et al. on Sep. 24, 2002, discloses an integrated external hydraulic trimming and steering system for an extended sterndrive transom assembly. A marine propulsion system is provided with a drive unit that is attachable to a transom of a marine vessel and provided with steering cylinder assemblies and trimming cylinder assemblies which are connected to a common location on a structural member, such as a gimbal ring.
U.S. Pat. No. 4,872,513, which issued to Meisenburg et al. on Oct. 10, 1989, discloses a marine sterndrive with a through-housing lubrication system. It includes an assemblage of a propeller carrying driveshaft housing, a bell housing and gimbal housing. Mating flow through passages are disposed in the driveshaft housing and bell housing, and a dual control valve system joins the passages at their juncture.
U.S. Pat. No. 6,561,859, which issued to Towner et al. on May 13, 2003, describes a marine engine assembly arm yoke and trunnion assembly. A steering arm yoke and trunnion assembly for a marine propulsion system includes a steering arm and a yoke including integral fluid paths for trim actuator fluids and for cooling water for an outboard powerhead mounted to a horizontal mounting plate within a platform extending from a boat hull. The steering arm and yoke include a drum extending through the horizontal mounting plate for rotating an attached propeller drive unit.
U.S. Pat. No. 6,186,845, which issued to Head on Feb. 13, 2001, describes a motor mounting structure for a boat. A mount for an outboard motor is disclosed in which the cylinder block of the motor is within the hull and the gear box and propeller are outside the hull. The driveshaft passes through the mount from the block to the gear box. The mount permits the motor to be swung from a horizontal axis to raise and lower the propeller.
U.S. Pat. No. 5,108,325, which issued to Livingston et al. on Apr. 28, 1992, discloses a boat propulsion device. The device is intended for a boat and mounts through a hole in a bottom surface of the boat. The engine is positioned inside the boat and the propeller drive is positioned under a bottom surface of the boat. The propulsion device includes a mounting assembly, a steering assembly rotatably connecting the drive to the mounting assembly for steering the propeller drive under the boat, a trimming assembly swingingly connecting the drive to the steering assembly for trimming/tilting of the propeller drive under the boat at any steering position, and a driveshaft means providing a drive connection between the engine and the propeller drive at any steered and trimmed position.
U.S. Pat. No. 6,609,939, which issued to Towner et al. on Aug. 26, 2003, describes a marine engine mounting assembly for a marine propulsion system. It includes a horizontal mounting plate, a pivot housing, and an adapter plate attached to one another through a plurality of vibration absorbing isolation points.
The patents described above are hereby expressly incorporated by reference in the description of the present invention.
It would be significantly beneficial if a sterndrive marine propulsion system could be preassembled and subsequently attached to a marine vessel as a unit, wherein the unit comprises the engine, the drive unit, and a transom attachment member.